As shown in FIG. 5, a prior art tricycle comprises two handlebars A1, a rear frame A2, and an intermediate frame A3 located between the handlebars A1 and the rear frame A2. The frames are fastened together by welding. The seat is fastened with a seat frame A4 which is engaged with the fastening seat A22 welded to a support tube A21 of the rear frame A2.
The prior art tricycle described above is intended for children, who are often unable to control the steering of the tricycle. For this reason, children must be taught by adults to control the operation of the handlebars. In the process of teaching children, the adults must hold the handlebars A1 from the behind to guide a child to steer the handlebars A1. Such a teaching process as described above is rather inconvenient as well as back-breaking as far as the adults are concerned. There must be a better way for an adult to engage in such teaching activities.